Systems and methods for a protective casing

ABSTRACT

Systems and methods for a protective casing are provided. In at least one embodiment, a protective casing includes a flexible insulation layer configured to inhibit thermal energy from conducting from an external side of the flexible insulation layer to an internal side of the flexible insulation layer. The protective casing also includes a microlattice layer abutting the internal side of the flexible insulation layer, the microlattice layer configured to distribute thermal energy that passes through the flexible insulation layer substantially throughout the microlattice layer. Further, the protective casing includes a heat absorbing material that impregnates the microlattice layer, the heat absorbing material configured to absorb the thermal energy in the microlattice layer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is related to the following co-pending United Statespatent application, which is hereby incorporated herein by reference:

U.S. patent application Ser. No. 13/552,275 entitled “SYSTEMS ANDMETHODS FOR PROTECTING A FLIGHT RECORDER” filed on even date herewithand which is referred to herein as the '156 application.

BACKGROUND

Certain environments and events cause extreme conditions that are notpresent in a normal environment. In particular, certain environments andevents can cause objects in that environment to experience extremeshocks, temperatures, and exposure to liquid such that the object can bedamaged. For example, data gathering instruments, that are susceptibleto the extreme forces in the environment, may need to pass through theseextreme environments in order to acquire and preserve the data for whichthe data gathering instruments are designed. Further, at times humansmay need to pass through extreme environments that could potentially belethal. To withstand these extreme conditions, objects can be insulatedfrom the heat by relatively brittle insulating materials and relativelyuncompressible heat absorbing materials. Generally, the insulatingmaterial surrounds a layer of heat absorbing material, where the heatabsorbing material surrounds the data gathering instrument. Further, incertain situations, due to the brittleness and incompressibility of theinsulating and heat absorbing material, an object is enclosed inheavy-gauge hardened steel to provide protection against shocks.

Due to the weight of the steel, an optimization process is used toreduce the total enclosed volume and weight of the enclosure while stillproviding the desired protection against extreme conditions. However,optimization of the enclosure geometry for structural robustness andpractical limitations on the dimensions of the data storage device leadto uneven distribution of insulation and/or heat absorbing material.Further, in certain embodiments, a steel enclosure accounts forapproximately 65% of the weight of the protective covering enclosing theprotected object.

SUMMARY

Systems and methods for a protective casing are provided. In at leastone embodiment a protective casing includes a flexible insulation layerconfigured to inhibit thermal energy from conducting from an externalside of the flexible insulation layer to an internal side of theflexible insulation layer. The protective casing also includes amicrolattice layer abutting the internal side of the flexible insulationlayer, the microlattice layer configured to distribute thermal energythat passes through the flexible insulation layer substantiallythroughout the microlattice layer. Further, the protective casingincludes a heat absorbing material that impregnates the microlatticelayer, the heat absorbing material configured to absorb the thermalenergy in the microlattice layer.

BRIEF DESCRIPTION OF THE DRAWINGS

Features of the present invention will become apparent to those skilledin the art from the following description with reference to thedrawings. Understanding that the drawings depict only typicalembodiments and are not therefore to be considered limiting in scope,the invention will be described with additional specificity and detailthrough the use of the accompanying drawings, in which:

FIG. 1 is a block diagram illustrating a cross section of a protectivecasing according to one embodiment;

FIG. 2 is a diagram illustrating a section of truss elements used toconstruct a microlattice layer according to one embodiment;

FIG. 3 is a block diagram illustrating a cross section of a protectivecasing according to one embodiment; and

FIG. 4 is a flow diagram of a method for constructing a protectivecasing according to one embodiment.

DETAILED DESCRIPTION

In the following detailed description, embodiments are described insufficient detail to enable those skilled in the art to practice theinvention. It is to be understood that other embodiments may be utilizedwithout departing from the scope of the invention. The followingdetailed description is, therefore, not to be taken in a limiting sense.

Embodiments of the present disclosure provide methods and systems forproviding protection to objects in environments with extreme conditions,such as the extreme conditions present during an aircraft disaster.

FIG. 1 is a diagram illustrating the components of a protective casing100 according to one embodiment. Protective casing 100 includescomponents that provide protection in extreme environments within aprotection compartment 102. For example, protective casing 100 canprovide protection to data gathering instruments such as a memory unitfor a flight data recorder, a scientific instrument, or a safe. Whenprotective casing 100 provides protection to a memory unit for a flightdata recorder, during normal operation of the memory unit, the memoryunit is connected to a communication cable that extends through theprotective casing 100. In an alternative implementation, when protectivecasing 100 provides protection to data gathering instruments, theportion of the instrument contained within protection compartment 102 isconnected to an external portion of the data gathering instrument thatis external to protective casing 100. Because objects within theprotection compartment 102 can be susceptible to damage caused byshocks, heat, and exposure to liquids, the protective casing 100includes protective structures that inhibit heat and shocks fromaffecting the objects inside the protection compartment. For example, asillustrated in FIG. 1, the protective casing 100 can include an innermetallic microlattice layer 112, a flexible insulation layer 116surrounding microlattice layer 112, and an outer protective layer 114surrounding insulation layer 116. In at least one embodiment, theprotective casing 100 includes heat absorption material 104 withinmicrolattice layer 112 that surrounds the protection compartment 102.

Microlattice layer 112 is a layer that encapsulates the protectivecasing in a metallic microlattice. In some embodiments, the metallicmicrolattice is a three-dimensional microstructure. In furtherembodiments, the microlattice is a structure that can be used as asupporting scaffolding in an apparatus for storing thermal energy, wherethe microlattice layer 112 includes a thermal storage material and themicrolattice supporting scaffolding.

FIG. 2 is a diagram illustrating a section 200 of a plurality of trusselements 202 that are used to form the microlattice supportingscaffolding. In at least one exemplary embodiment, the section 200includes eight different truss elements 202 that are joined together ata node 204. The section 200 of truss elements 202 can include more orless than eight different truss elements 202 in other embodiments. Asshown in FIG. 2, the truss elements 202 interpenetrate each other at thenode 204 to form the section 200. The microlattice supportingscaffolding in microlattice layer 112 in FIG. 1 is formed by multiplesections 200 that are joined together to form a continuous latticestructure.

In one embodiment, multiple truss elements 202 in section 200 are formedcontinuously such that the interior of two conjoined truss elements 202,within the section 200, forms a contiguous void having no interiorboundaries. When the interior of the different truss elements 202 lacksinterior boundaries, the nodes 204 connecting the different trusselements 202 is made of the same material as the material used tofabricate the truss elements 202.

The truss elements 202 in section 200 have an intrinsically highstrength due to the small size of the truss elements 202. Further, thetruss elements 202 are configured to have a correspondingly small aspectratio (e.g., length/diameter ratio) for withstanding a bending moment.Also, as microlattice layer 112 in FIG. 1 is formed from multipleconjoined sections of truss elements 200, microlattice layer 112 is ableto withstand mechanical loads via axial tension and compression of thetruss elements in section 200. Molecular alignment of the truss elements202 along their respective axial directions lends additional strengthand/or stiffness to the truss elements 202 and, accordingly, also tomicrolattice layer 112. Further, in at least one implementation, thetruss elements 202 are configured to provide the microlattice layer 112in FIG. 1 with a stretch-dominated behavior under a compression loadapplied to microlattice layer 112.

As illustrated in FIG. 2, truss elements 202 respectively extend indifferent directions away from node 204. For example, according to atleast one embodiment, section 200 may include eight truss elements 202,each of which extends along a corresponding one of eight varyingdirections away from the node 204. In at least one implementation, theeight truss elements 202 interpenetrate one another at node 204 to forma section of continuous material.

In certain implementations, when multiple sections of truss elements 200are joined together to form a microlattice layer, like microlatticelayer 112 in FIG. 1, a significant portion of the microlattice layer 112is free space. In certain implementations, the free space within themicrolattice layer 112 is filled at least partially with a materialdifferent from the material of the microlattice structure itself. Forexample, the free space within microlattice layer 112 can be filled witha material that absorbs thermal energy, where the microlatticesupporting scaffolding within microlattice layer 112 distributes thethermal energy substantially evenly throughout the absorbing material inthe free space within microlattice layer 112.

In at least one embodiment, microlattice layer 112 is fabricated toabsorb thermal energy by providing a metallic microlattice as athree-dimensional ordered open-cellular structure that functions as ascaffold. The open cells are then filled with a phase change material.Examples of suitable phase change materials are hydrocarbons, organicmolecules, fatty acids, salt hydrates, bicarbonates of soda, and thelike. In at least one implementation, an object is protected within theprotection compartment by heat absorption material 104. For example, theheat absorption material 104 can be a phase change material thatsurrounds the protected object within the microlattice layer 112. Heatabsorption material is further described in the following United StatesPatents all of which are incorporated by reference: U.S. Pat. No.5,932,839, entitled “METHOD FOR DISSIPATING HEAT AWAY FROM HEATSENSITIVE DEVICE USING BICARBONATE COMPOSITIONS” filed on Nov. 4, 1997,referred to herein as the '839 patent; U.S. Pat. No. 6,078,011, entitled“METHOD FOR DISSIPATING HEAT AWAY FROM A HEAT SENSITIVE DEVICE USINGBICARBONATE COMPOSITION” filed on May 6, 1999, referred to herein as the'011 patent; and U.S. Pat. No. 6,899,161, entitled “METHOD FOR HEATABSORPTION USING POLYOXYMETHLENE POLYMER COMPOSITIONS” filed on Apr. 3,2003, referred to herein as the '161 patent.

In certain embodiments, the protective compartment 102 and themicrolattice layer 112 are enclosed within a flexible insulation layer116. The flexible insulation layer 116 inhibits the transfer of heatthrough the flexible insulation layer 116 to protect objects within theprotective compartment 102 from a heated environment containing theprotective casing 100. For example, when the protective casing 100 is ina heated environment, the flexible insulation layer 116 inhibits thetransfer of heat through the flexible insulation layer 116 to themicrolattice layer 112. The heat that does get transferred through theflexible insulation layer 116, is absorbed by heat absorption materialthat is contained within the microlattice layer 112. The combination ofthe flexible insulation layer 116 and the microlattice layer 112function jointly to inhibit heat in the environment of the protectivecasing 100 from damaging objects within the protective compartment 102.

Further, the combination of flexible insulation layer 116 andmicrolattice layer 112 function jointly to prevent shocks to theprotective casing 100 from damaging objects within the protectivecompartment 102. In one exemplary implementation, the flexibleinsulation layer 116 comprises a layer of flexible aerogel or otherflexible insulator. In at least one implementation the flexible aerogellayer 116 is PYROGEL XTF. Flexible insulation layer 116 is deformableand able to move in response to shocks. Further, microlattice layer 112is also deformable and able to move in response to shocks. Due to thedeformability and ability to absorb shocks of both the flexibleinsulation layer 116 and the microlattice layer 112, the flexibleinsulation layer 116 and microlattice layer 112 are able to absorbenergy produced by shocks applied to the protective casing 100 andprevent the shocks from damaging objects within the protectivecompartment 102.

Further, to protect objects within the protective compartment 102 fromfurther damage when the protective casing 100 is exposed to extremeconditions, the protective casing 100 can include outer protective layer114. Outer protective layer 114 is a hard layer that is designed towithstand impacts at the high forces present in conditions like vehiclecrashes, or falls from high elevations. For example, outer protectivelayer 114 can be fabricated from a metal, a composite material (e.g., acarbon composite), or the like. In certain implementations, thecombination of the flexible insulation layer 116 and the microlatticelayer 112, which both have shock absorbent qualities, allow for athinner outer protective layer 114 than would be possible if theflexible insulation layer 116 was brittle and the microlattice layer 112was not deformable. The thinner outer protective layer 114 reduces thesize and weight of the protective casing 100. Thus, the combination ofthe outer protective layer 114, the flexible insulation layer 116, andthe microlattice layer 112 function together to protect an object fromforces present in extreme environments.

In certain embodiments, the protective casing 100 is designed towithstand the extreme environment that occurs during aircraft disasters.To ensure that the protective casing is able to withstand the extremeenvironment of an airplane crash, the protective casing 100 isrigorously tested. For example, the protective casing can be designed towithstand a crash impact of 3,400 Gs. The protective casing 100 can alsobe made resistant to penetration, as the most vulnerable axis of theprotective casing 100 can be made to withstand the force caused by thedrop of a 500 pound weight with a 0.25 square inch pin protruding fromthe bottom of the weight from a height of ten feet. Further, theprotective casing 100 can also be made to withstand temperatures of1100° C. for at least an hour. The protective casing 100 can alsoundergo other tests to determine the resistance of the protective casing100 to pressure, liquid, and chemical forces that may be present in theevent of an aircraft disaster. The components of the protective casing100 function together to withstand the extreme environments that existduring an aircraft crash and the above described rigorous testing.

FIG. 3 is a block diagram illustrating a protective casing 300 that isdesigned to provide flexible protection to an object 302. In certainsituations the object 302 to be protected by protective casing 300flexes and moves. For example, a fireman or other user who works in anextreme environment may need protection from conditions present in theextreme environment. To protect the user, the protective casing 300 isimplemented into clothing for the user. As described above, theprotective casing 300, like protective casing 100, can include amicrolattice layer 312 and a flexible insulation layer 316. Microlatticelayer 312 and flexible insulation layer 316 function similarly tomicrolattice layer 112 and flexible insulation layer 116 in FIG. 1. Asboth microlattice layer 312 and flexible insulation layer 316 arebendable, they can be implemented into a flexible protective casing 300such as a textile material.

In certain implementations, the protective casing 300 includes an outerprotective layer 314. The outer protective layer 314 provides protectionto the object 302 within the protective casing 300 according to theenvironment in which the user will primarily operate. For example, theouter protective layer 314 can provide further protection against heat.Alternatively, the outer protective layer 314 can be made from apuncture resistant material. Further, the outer protective layer 314 canbe made from a waterproof material. In at least one implementation, theouter protective layer 314 is made from a composite material or multiplelayers of materials that provide protection against multipleenvironments. In at least one embodiment, the outer protective layer 314is on the sides of the protective casing 300 that are both nearest theobject 302 and farthest from the object 302.

FIG. 4 is a flow diagram of a method 400 for fabricating a protectivecasing according to one embodiment. Method 400 proceeds at 402 where ametallic microlattice layer is placed around a protected object. Asdiscussed above, the metallic microlattice layer is a structure of trusselements that can provide a compressible scaffolding layer around theprotected object. Method 400 proceeds at 404, where the metallicmicrolattice layer is impregnated with a heat absorption material. Theheat absorption material can include a phase change material such as abicarbonate of soda, or other phase change material. The metallicmicrolattice layer distributes heat throughout the heat absorptionmaterial to impede thermal energy from reaching the protected object.

Method 400 proceeds at 406 where a flexible insulation layer is placedaround the metallic microlattice layer that is impregnated with the heatabsorption material. For example, a layer of flexible aerogel can beplaced around the metallic microlattice layer. The flexible aerogelimpedes the transfer of heat from the external layers of a protectivecasing to the inner layers surrounding the protected object. Method 400proceeds at 408 where an outer protective layer such as an impactresistant layer is formed around the flexible insulation layer. Forexample, the impact resistant layer absorbs shocks to the protectivecasing and encapsulates the metallic microlattice layer and theinsulation layer. The combination of the multiple layers of theprotective casing that surround the protected object protect the objectfrom forces caused by extreme environments.

Example Embodiments

Example 1 includes a protective casing, comprising a microlattice layerconfigured to surround an object and impregnated with a heat absorbingmaterial; a flexible insulation layer that surrounds the microlatticelayer; and an outer protective layer that surrounds the flexibleinsulation layer.

Example 2 includes the protective casing of Example 1, wherein the heatabsorbing material comprises at least one of a polymer; a silica gel; abinder; and a phase change material.

Example 3 includes the protective casing of Example 2, wherein the phasechange material comprises at least one of a hydrocarbon; an organicchemical; a fatty acid; a salt hydrate; and a bicarbonate of soda.

Example 4 includes the protective casing of any of Examples 1-3, whereinthe flexible insulation layer comprises at least one of an insulativewool; a foam; a flexible aerogel.

Example 5 includes the protective casing of any of Examples 1-4, whereinthe outer protective layer comprises a metal.

Example 6 includes the protective casing of Example 5, wherein the outerprotective layer is deformable.

Example 7 includes the protective casing of any of Examples 1-6, whereinthe outer protective layer comprises a fabric.

Example 8 includes the protective casing of any of Examples 1-7, whereinthe outer protective layer comprises a composite material.

Example 9 includes the protective casing of any of Examples 1-8, whereinthe object is selected from the group consisting of a human; ascientific instrument; a data recorder; and a safe.

Example 10 includes a method for fabricating a protective casing, themethod comprising placing a metallic microlattice layer around aprotected object; impregnating the metallic microlattice layer with aheat absorption material; placing a flexible insulation layer around themetallic microlattice layer that is impregnated with the heat absorptionmaterial; and forming an outer protective layer around the flexibleinsulation layer.

Example 11 includes the method of Example 10, wherein the flexibleinsulation layer is comprised of a flexible aerogel.

Example 12 includes the method of any of Examples 10-11, wherein theheat absorption material comprises a phase change material.

Example 13 includes a protective casing, the casing comprising aflexible insulation layer configured to inhibit thermal energy fromconducting from an external side of the flexible insulation layer to aninternal side of the flexible insulation layer; a microlattice layerabutting the internal side of the flexible insulation layer, themicrolattice layer configured to distribute thermal energy that passesthrough the flexible insulation layer substantially throughout themicrolattice layer; and a heat absorbing material that impregnates themicrolattice layer, the heat absorbing material configured to absorb thethermal energy in the microlattice layer.

Example 14 includes the protective casing of Example 13, furthercomprising an outer protective layer abutting the external side of theflexible insulation layer.

Example 15 includes the protective casing of Example 14, wherein theouter protective layer is configured to absorb impacts to the protectivecasing.

Example 16 includes the protective casing of any of Examples 14-15,wherein the outer protective layer is at least one of a textilematerial; a composite material; and a metal.

Example 17 includes the protective casing of any of Examples 13-16,wherein the heat absorbing material is a phase change material.

Example 18 includes the protective casing of any of Examples 13-17,further comprising an additional heat absorbing material that isencapsulated within the microlattice layer and enveloping the protectedobject.

Example 19 includes the protective casing of any of Examples 13-18,wherein the protective casing is configured to protect an objectselected from the group consisting of a human; a scientific instrument;a data recorder; and a safe.

Example 20 includes the protective casing of any of Examples 13-19,wherein the flexible insulation layer is a flexible aerogel layer.

The present invention may be embodied in other specific forms withoutdeparting from its essential characteristics. The described embodimentsare to be considered in all respects only as illustrative and notrestrictive. The scope of the invention is therefore indicated by theappended claims rather than by the foregoing description. All changesthat come within the meaning and range of equivalency of the claims areto be embraced within their scope.

What is claimed is:
 1. A protective casing, comprising: a metallic microlattice layer configured to surround an object and impregnated with a heat absorbing material, wherein the metallic microlattice layer comprises a layer of supporting scaffolding formed by a plurality of conjoined sections of truss elements; a flexible insulation layer that surrounds the metallic microlattice layer; and an outer protective layer that surrounds the flexible insulation layer.
 2. The protective casing of claim 1, wherein the heat absorbing material comprises at least one of: a polymer; a silica gel; a binder; and a phase change material.
 3. The protective casing of claim 2, wherein the phase change material comprises at least one of: a hydrocarbon; an organic chemical; a fatty acid; a salt hydrate; and a bicarbonate of soda.
 4. The protective casing of claim 1, wherein the flexible insulation layer comprises at least one of: an insulative wool; a foam; a flexible aerogel.
 5. The protective casing of claim 1, wherein the outer protective layer comprises a metal.
 6. The protective casing of claim 5, wherein the outer protective layer is deformable.
 7. The protective casing of claim 1, wherein the outer protective layer comprises a fabric.
 8. The protective casing of claim 1, wherein the outer protective layer comprises a composite material.
 9. The protective casing of claim 1, wherein the object is selected from the group consisting of: a human; a scientific instrument; a data recorder; and a safe. 